[ https://issues.apache.org/jira/browse/HADOOP-9086?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Allen Wittenauer resolved HADOOP-9086. -------------------------------------- Resolution: Won't Fix I'm going to set this as won't fix. Introducing more dependencies at this level sounds like a bad thing, esp given that every ops person has their own preferences as to what to user here. > Enforce process singleton rules through an exclusive write lock on a file, > not a pid file +kill -0, > --------------------------------------------------------------------------------------------------- > > Key: HADOOP-9086 > URL: https://issues.apache.org/jira/browse/HADOOP-9086 > Project: Hadoop Common > Issue Type: Improvement > Components: scripts, util > Affects Versions: 1.1.1, 2.0.3-alpha > Environment: Unix/Linux. > Reporter: Steve Loughran > > the {{hadoop-daemon.sh}} script (and other liveness monitors) probe the > existence of a daemon service by a {{kill -0}} of a process id picked up from > a pid file. > This is flawed > # pid file locations may change with installations. > # Linux and Unix recycle pids, leading to false positives -the scripts think > the process is running, when another process is. > # doesn't work on windows. > Having the processes acquire an exclusive write-lock on a known file would > delegate lock management and implicitly liveness to the OS itself. when the > process dies, the lock is relased (on Unixes) -- This message was sent by Atlassian JIRA (v6.3.4#6332)